New Enzyme System-Beta-Amylase-Pullulanase-To Determine the Degree of Gelatinization and Retrogradation of Starch or Starch Products

A sensitive method to determine the change of degree of gelatinization during storage of starch products was studied. A new enzyme system consisting of beta-amylase-pullulanase was established for this purpose and named as BAP method. Beta-amylase is known not to react on raw starch and pullulanase is also known to be strongly affected by the degree of dispersion of amylopectin molecule in a solution. The new enzyme system clearly differentiates the velocity of hydrolysis between gelatinized starch and retrograded one compared with the conventional glucoamylase system. This enzyme system is particularly useful to determine the retrogradation of starchy food during storage.